Ophthalmic instrument for and method of applying the hirsch eye test



Sept. 28 1926..

c. L.. HuNslcKER OPHTHALMIG INSTRUMENT FOR AND METHOD OF APPLYING THEHIRSCH EYE TEST Slept. 28 1926. 1,601,394

C. L. HUNSICKER OPHTHALMIC INSTRUMENT FOR AND METHOD `0T APPLYING THEHIRscH EYE TEST Fil'ed Nov. 14, 1925 2 sheets-sheet 2 INVENTOR CLY DELHUNSIC KER ATTORNEY Patented Sept. 28, 1926.

UmrEn sTATEs CITYDE L. HUNSICKER, OF SAN FRANCISCO, CALIFORNIA.

1,601,394 PATENT OFFICE.

OPHTHALMIC INSTRUMENT FOR AND lwlllI-IOI)V OF APPLYING THE HIRSCH EYETEST.

The present invention relates to improvements in means for applying theHirsch test for eye-strains, and has reference more particularly to thattype employing the pantographic principle as an aid to ypatients undergoing examinations for such ailments in recording their efforts atmuscular co-ordi nation in attempts at accurately locating points, orcharacters, upon a specially prepared cha-rt. y A principal object of myinvention is the provision of an instrument and a means forv itspositive application in connection with the -Hirsch eye-strain test,whereby a patient may subject himself to an eye-muscle test fordetermining their normal co-ordination, or the degree of departuretherefrom.

A further object of the invention is theV provision of a simple andefficient means for applying the Hirsch test for eye-strain andregistering the departure from normal muscular co-ordination upon 'asuitably prepared and arranged duplicate chart, as indicated through acorrelated pantographic action.

Additional to that of the foregoing is to provide a simpler, moreeliicient and accurate means for applying the Hirsch eye-test, indetermining lack of, or ineicient, co-ordination of eye-muscles, inendeavors to orientate thek position of points upon a fixed chart andthe recordation of variency from normalcy upon an accompanyingduplicatechart.

The instrument as here devised is of such simplicity of construction andpositiveness and accuracy of operation as to be entrusted to anattendant, thus relieving thespecialisty of a personal supervision ofthe test, as is now required.

In applying the Hirsch test for eye strain, there is employed a simplechart of black background divided into squares by intersecting lines,with these points of intersection marked by red kdots or indicia. Thelchart thus prepared is placed before the patient Whose eyes are to betested, the eyes being provided with ray-lters of red and green, withthe red yfilter placed over the eye to-be tested. The patient is nextprovided with a pointer and directed to place the point thereof uponadesignated or selected red in'- dicia, the reds being clearlydiscernable through the red filter, while, when viewed through the greenfilter, these red indicia become undistinguishable, the vgreen filterApplication filed November 14, 1,925. SeralNo. 68,946.

causing them to blend with the black background. The patients degree oflack ofac` curacy in correctly orientating as between pointer point andthe designated indicia, or in placing the pointer point upon theparticular point selected, is taken as the gauge of the patients eyenormalcy or the degree of departure therefrom.

In the accomplishment of the purposes, as set forth, there is employedthe usual Hirsch chart of black back-ground bearing red dots arranged ascorners of squares, supported by a frame and stand carrying apantographic element, an actuating mechanism controlling thepantographic movement, a locking element, an indicator, charts induplicate, a recording element, and a pedestal bearing anadjustablechin-rest and a supporting means for color-screens of red andgreen for either eye.

In the accompanying drawings, constituting a part of this specification,and in which similar reference characters refer to like parts,throughout,-

Figure l is a frontelevation of the device, showing the supportingframe, pantographic element, actuating mechanism for the control of thepantographic element, fixed orientation chart, removable duplicate.recording charts, and the orientation indicator-point borne by thepantographic element, represented as centrally located at the upper edgeof the orientation chart;

Figure 2 is a side 'elevation of the device, showing the relativepositions of the pantographic levers, link' connections, actuating meansfor controlling the pantographic ele-V ments, locking means for securingthe levers in locked relationship, manually operable means for recordingselected locations upon the recording charts, and an adjustable meanscarrying a chin-rest and colored eyescreens; r I

Figure 3 is an enlarged sectional detail of the locking means forlocking the pantographic levers in fixedy relationship, While therecording means is being manually actuated to record the oriented pointupon the recording chart; and

Figure 4L is a diagrammatic view of the color-screens used in connectionwith the instrument. Y

- Referring with greater particularityto the drawings, and moreparticularly to Figures 1 and 2, the instrument comprises a supportingtrame 1, preterably of cast construction; a pantographic element 2; anactuating nechanism 3, controlling the pantographic movement of theelement 2; a locking element 4, adapted to lock the pantographic element2 in recording` position; an indicator-recording mechanism 5, actuatedby the movement of the pantographic element and in co-ope'rativeassociation with a chart-bearing member 6 tor recordation purposes; anorientation chart 7; and a supporting means 8 tor color-screens.

rlhe supporting trame 1 is, preferably, of rectangular torni andconsists ot abase 9, uprights 16, front brackets 11 and rear uprightextension members 12. rl`he pantographic element 2 consists of a pair otlevers 13 and 14 pivotally secured in the trame 1 by the shaft 15, whichis mounted in suitable bearings integrally borne by the tramecross-braces 16 and 17. The levers 18 and 14 are adapted to swing, oroscillate, about the shaft 15 and consist of bridged lower Y extremities18 and 19 connected by braces 2O and adapted to oscillate the one Withinthe other, as shown in Figure 2. rEhe ef;- tremities 18 and 19 of thelevers 13 and 14 are connected at the pivot points 21 and 22 by'a pairot bridged link-connections 23 and 24, which are connected at theirlower ends by the pintle 25. The levers 13 and i4 are pivotallyconnected' at the points 26 and 27' to a second pair ot levers 2S and29, which levers are pivotally connected together at their upper ends,as shown at 30. Y The point 8O of the pantographic element 2 is adaptedfor vertical movement relative to the shaft 15 and for lateraloscillation relative to said shalt, through the action oi" the actuatingmechanism 3, which mechanism consists of a hand-lever 31 ot bellcrankform bearing a bifurcated lower end 32 adapted to embrace the lower endot said shaft 15, to which it is connected by a rigid arm 33 pinned tothe shaft at 34 and pivotally bearing the bifurcated end ot the lever.as indicated at 35, the lower end of said lever being connected to thepintle et the pantographic element 2by a linl; connection 36and'swivel-bracket 37.

rlhe locking mechanism 4 consists oit a means for locking thepantographic element 2 and the auxiliary indicater-recording mechanismin position preliminary to the actuation ol' the chart-bearing member 6,and comprises clamp-members 38 pivotally secured to the ears 39, formedintegrally With the frame cross-piece 40, by the pintle 41. rlheclamp-member 38 is in the term of a bell-crank and is adapted to be heldin operative position by means of the compression spring 42 seated in anaperture 43 formed in the cross-piece 40. rlhe clampmember is heldnormally inoperative by means ot a link connection 44 piv-otally con-Leonesa nected at its upper end to a short crank-arm 45 rigidly borne bythe rod 46, said rod being in turn borne by the 'trame uprights 16. Anoperating lever 47 is secured upon the outer end olf the rod 46 andnormally bears against a pin 4S mounted in its path when. the arm 45 andconnecting pivotal pointlol the linl: 44 pass over the center ot the rod46.

rlhe end of the pintle 21 adjacent Jdie loclring mechanism 4 is providedwith a seg ment ot arcuate form loosely mounted thereon and adapted totravel in an arcuate course with the extremity 18 ot the arm 14 or thepantographic element, the opposite end 50 oli' .said segment beingprovi-ded with an arcuate slot 51 adapted to accommodate the pintle 22but to allow of tree movement thereon, said segment being adapted foroscillating movement with the pantograph, but at all times travelling inthe aperture 52 :termed between the cross-piece 46 oit the frame and theclan'ip-men'iber 39 ot the locle4 ing mechanism, so that upon release otthc lever 47, to the dot-and-dash position shown in Figure 3, theclamp-member 38 is released and co-acts with the member 40 totr'ctionally grip the segment 49 and hold the levers 13 and 14 in anydesired position.

rlhe auxiliary recording mechanism 5 consists ot a pair o'tl shortlevers 53 vand :34 pivotally secured to the levers 13 and 14 acent theshaft 15, and pivotally connected together at their upper ends, asindicated at 55, Which point is at all times in alignmentV With thecenters 30 and 15 of the element 2. A prick-point 56 entends rear-Wardly from the pivot point and travels in a ratio ot l to 4 relative tothe point SO. rElie chart-bearing member 6 comprises a rectangular plate57 hingedly secured to the rear oit the trame 1 by the rod 56 andadapted to swing from horizontal tol vertical po'- sition, asshown inFigure 2, into contact with the prick-points 56, but normally restingagainst a removable stop 5e s shown in.

full lines., rllie inner tace ot the plate 54 preferably veneered, asindicated at 60, for the reception oit a pair ot recording charts 6l and62, one tor each eye ot patiert, the right chart 62, Figure 1, beingshoiv'n cen-- trally located upon the plate 57'i'n readiness tor recordreceiving and secured thereto by any suitable means -readily releasable.Y Each chart is provided With a number ot equally spaced lines scored atright angles to each other, forming sixteen squares carrying dots 63their points of intersection. Though so shown here, it is obvious thatintersecting circular lines with intersections thus marked would servethe purpose equally Well. The orientation chart 7 is a fixed black-board64 secured in place against the upper ends oi the upright members 12 otthe r'trame 1, is oit rectangular farm and scored to contorni to that ofthe recording charts 6l and 62,

lll() lll) except that the squares are four times the size of those ofthe recording chart.

' The dots or indicia of the orientation chart 7 being in red areclearly discernable when viewed through the red screen, while, if viewedthrough the green screen, they become -undistinguishable, blending withthe black of the background, conditions requiring that the eye to betested be covered by the red screen 68er the card `67, with the greenscreen 66 covering the other eye.

The supporting means 8 comprises a pedestal 69 adapted to rest upon thetable-top 70, supported by the brackets ll off-'the trame l, saidpedestal bearing an adjustable rod 7l bearing at its upper end achin-rest 72 and an extension 73 bearing the card 67 carrying thecolor-screens 66 and 68 in convenient arrangementfor use by the patient,as shown in Figure 2. The supporting means may be adjusted to meetrequirements, as may also the frame l, by means of the screw-adjustment74, which may be mounted upon any convenient standard (not shown). r[hetable-top 7 O is provided with an opening 7 5, through which thehand-lever 81 extends and allows of its free movement in themanipulation of the pantographic element 2.

The operation of the apparatus is as follows: Assuming any point, as 76,Figure l, as conveniently located and selected for applying the test,and the patient in position, as .indicated in Figure 2.

The patient is instructed to direct his eyes upon the chart 7 and withhis hand grasping the lever 3l, endeavor to move the pantographicelement 2, through its associate actuating element 3, in such manner anddiverse directions as will bring the indicator point 30 into apparent,or actual, registration with the selected point 76. Upon theaccomplishmentot this action, the patient rests his efforts and theattendant immediately locks the actuating mechanism, or element, inposition, through the thrown and gripping' action of the lockingmechanism 4, and follows this with swinging the plate 57 from the fullline position, shown in Figure 2, to the vertical dotted position andinto contact with the prick-points 56, thereby recording upon the chart62 a point corresponding in position to that indicated by the indicator30 upon the chart 7. The test, as provided for, may be applied to eithereye and repeated indefinitely, registering each attempt at accuracy inorientation, or bringing a movable point into registration with a fixedone, there being provided a separate registration chart for each eye,for later reference in determining their variance from perfectregistration, as an indeX to the degree of lack of co-ordination ofnormal character in the muscles governing the movements of the eye.

The lower ends of the levers 13 and 14 and links 23 and 24 constitutingthe pantographic element are weighted to counter-balance the levers 28and 29 and normally retain point 30 substantially'as shown in Figure l.

I claim: y

l.. In a device of the character described, the combination with anorientation chart, of a pantographic element adapted to locatepointsup'on said chart, means for the manual actuation of saidpantographic element, and means for locking said pantographic element atthe instant of location of a selected point.

2. In a device of the character'described, the combination ot anorientation chart, a pantographic element, an indicating means carriedby said pantographic element, means for manually actuating saidpantographic element, means for locking said element, a recording chart,and means adapted to register points upon said recording chartcorresponding in position to those indicated upon said orientationchart.

8. In a device of the character described, the combination, anorientation chart bearing a plurality of intersecting lines having dotsat their points of intersection, and a pantographic element adapted fortracing courses and locating points upon said orientation chart.

4. In a device of the character described, the combination, with anorientation chart bearing a plurality of intersecting lines having dotsaty their points of intersection, of a pantographio element bearing anindicator and adapted for tracing courses and locating points upon saidchart, a recording chart the facsimile or said orientation chart, andmeans for the operation of said pantographic element relative to bothsaid orientation chart and recording chart.

5. In a device of the character described, the combination, with anorientation chart bearing a plurality of intersecting lines havving dotsat their points of intersection, of a pantographic element bearing anindicator and adapted for tracing courses and locating points upon saidchart, a recording chart the facsimile of said orientation chart and iniiXed and similar relationship thereto, meansy for manually actuatingsaid pantographic element relative to both said orientation chart andrecording chart, and means for locking said pantographic element at anydesired point in its movement.

6. In a device of the character described, the combination, with anorientation chart bearing a plurality of intersecting lines hav- 'ingdots at their points of intersection, of a pantographic element bearinga point indicator and adapted for tracing and locating points upon saidchart, a recording chart the facsimile of said orientation chart and inco-ordinate arrangement therewith, means :tor manually actuating saidpantographic element relative to Vboth said orientation chart undrecording` chart, means for locking said pantographic element at anydesired point in its movement, and means adapted to register points uponsaid recording chart corresponding in position to those as indicatedupon said orientation chart.

7. In a 'device of the character described, the combination, with anorientation chart, of a counter-balanced pantographic element adapted tolocate points upon said chart, lever and link connections 'for thenormal manual actuation of said pantographic element, and means forlocking said pantographie element at the instant of location oi' aselected point.

8. In a device of the character described, the combination, with anorientation chart, of a counter-balanced pantographic element adapted toremain normally extended, manually actuated means, comprising alever andlinl connections, whereby the said element may be operated for thelocation of points upon the said chart, means for locking said elementat any selected point, and means for recording said selected point.

In testimony whereof I have afixed my signature. c

CLYDE L. IIUNSIGKER.

